The electric telegraph, together with the railway-train and the steamship, constituted the three most conspicuous features of late 19th century civilization. Indeed, it may be truly said that the harnessing electricity to the service of man for human communication has effected a change in political, commercial, and social relations, even more complete than that wrought by steam locomotion. This is the story of how the electric telegraph cable was laid across the floor of the Atlantic from Newfoundland to Ireland.
By : Sir Charles Bright (1863 - 1937)
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The Electric Telegraph—First Land Telegraphs—First Submarine Cables: Dover to Calais, 1850-’51—Other Early Cables: England to Ireland, 1853, etc.
The Electric Telegraph.—The advances made in electric science are so bold and rapid that our still comparative ignorance of the precise nature of electricity must always seem strange. We are not, however, here directly concerned with electricity as a physical science, but rather with its practical applications to the still present system of telegraphy, by way of introduction to the gradual development of Trans-Atlantic telegraphy. The electric telegraph, together with the railway-train and the steamship, constitute the three most conspicuous features of latter-day civilization. Indeed, it may be truly said that the harnessing of this force of nature (electricity) to the service of man for human intercourse has effected a change in political, commercial, and social relations, even more complete than that wrought by steam locomotion. Like its fellow emblems, the telegraph was the outcome of many years of persevering effort on the part of numerous scientific investigators and inventors; like them also, it was perfected for practical use on both sides of the Atlantic by men of our own race and speech, such as Cooke, Wheatstone, and Morse.
The First Land Telegraphs.—The first practical telegraph-line in the world—namely, that on the Great Western Railway from Paddington to West Drayton, shortly afterward extended to Slough—was within the year of Queen Victoria’s accession to the throne, and in the same year as the first trunk line of railway and the first ocean steamer. Improvements and novelties in telegraphic instruments were rapidly made by inventors from all the civilized nations—e. g., Morse, Vail, and Henry in America; Breguet in France; Steinheil and Siemens & Halske in Germany; and Schilling in Russia; besides Alexander Bain, Bright, and Hughes in England. Commercial interests were soon formed to work the new invention, and in England the Electric and International Telegraph Company, the British and Irish Magnetic Telegraph Company, and other large concerns were the means of establishing telegraphic communication throughout the kingdom—only to be absorbed by Government later on. Our theme does not include—even in the course of introduction—a study of the development of land telegraphy. The apparatus and methods employed are, to a great extent, entirely different; indeed, the only point in common between the cardinal principles and submarine telegraphy is that electricity, as generated by a voltaic battery, is the common agent, and consequently the metal conducting-wire is employed in both. But in subaqueous (as well as in subterranean) telegraphy the poles and porcelain insulators require to be substituted by an insulating covering round the entire conductor; and the point of contact in practise between land and marine telegraphy is really, therefore, in the matter of insulation for subterranean or subaqueous wires.
First Submarine Cables.—A Spaniard named Salva appears to have suggested the feasibility of submarine telegraphy as far back as 1795, and in 1811 Sommering and Schilling conducted a series of experiments, more or less practical, when a soluble material—said to have been india-rubber—was first used for insulating the wire.
But the earliest records of practical telegraphy under water of which there are any particulars relate to the experiments conducted by Dr. O’Shaughnessy (afterward Sir William O’Shaughnessy Brooke, F.R.S.) across the River Hugli on behalf of the East Indian Company in 1838. Referring to his practical researches a little later, O’Shaughnessy remarked: “Insulation, according to my experiments, is best accomplished by enclosing the wire (previously pitched) in a split rattan, and then paying the rattan round with tarred yarn; or the wire may—as in some experiments by Colonel Pasley, R.E., at Chatham—be surrounded by strands of tarred rope, and this by pitched yarn. An insulated rope of this kind may be spread across a wet field—nay, even led through a river—and will still conduct the electrical signals, without any appreciable loss.” In 1840 Professor Wheatstone (afterward Sir Charles Wheatstone, F.R.S.) explained to a committee of the House of Commons the methods by which he thought it possible to establish telegraphic communication between Dover and Calais. He appears to have been unaware of the prior experiments just alluded to, for his system of insulation, though more fully developed, was practically the same.
Prof. S. F. B. Morse, the well-known inventor of the telegraph apparatus bearing his name, also made a study of this problem in 1842, when he laid down an insulated copper wire across New York harbor, through which he transmitted electric currents. Hemp soaked in tar and pitch, surrounded with a layer of india-rubber, constituted the insulation. Morse was a great letter-writer, and records of his early work are solely based on his own statements at a time when he noted in his diary: “I am crushed for want of means. My stockings all want to see my mother, and my hat is hoary with age.” In 1845 Ezra Cornell, who was afterward the founder of Cornell University, laid a cable, twelve miles long, to connect Fort Lee with New York, in the Hudson River. The cable consisted of two cotton-covered copper wires, insulated with india-rubber, and enclosed in a leaden pipe. It worked well for several months, but was broken by ice in 1846. In that year Mr. Charles West paid out by hand an india-rubber insulated wire in Portsmouth harbor, through which he signaled from a boat to the shore. The experiment was intended as the forerunner of the establishment of telegraphic communication between England and France, but for want of the necessary funds was not followed up.
Subaqueous, or marine, telegraphy owed its institution, however, to the introduction of gutta-percha, for insulating purposes. The late Dr. Werner Siemens having invented a machine for applying gutta-percha to a wire—similar in principle to the machine for making macaroni—considerable lengths of gutta-percha-covered subterranean wires were laid in Germany and Prussia between 1846 and 1849; and in 1849 Siemens laid a gutta-percha insulated conductor in the harbor of Kiel which was used for firing mines. Following this came the extensive system of underground lines laid down in England for the Magnetic Telegraph Company by their engineer, Mr. (afterward Sir Charles) Bright, in accordance with a patent of his. Short lengths were also laid, mostly through tunnels, by the Electric Telegraph Company a little later.
On the 10th day of January, 1849, the late Mr. C. V. Walker, F.R.S., electrician to the Southeastern Railway, laid a gutta-percha-covered conductor, two miles long, in the English Channel. The wire was coiled on a drum on board the laying vessel, from which it was paid out as the vessel progressed. Starting from the beach at Folkestone, the line was joined up to an aerial wire, 83 miles in length, along the Southeastern Railway, and Mr. Walker, on board the Princess Clementine, succeeded in exchanging telegrams with London.
On the 23d July, 1845, the brothers Jacob and John Watkins Brett addressed themselves to Sir Robert Peel, as Prime Minister and First Lord of the Treasury, relative to a proposal of theirs for establishing a general system of telegraphic communication—oceanic and otherwise. They were referred to the Admiralty, Foreign Office, etc., and gradually became involved in a departmental correspondence—more academic than useful—in which they were passed backward and forward from one government office to another. After considerable negotiations with both governments concerned, a concession was at last obtained by the Messrs. Brett, and a company formed for instituting telegraphy between England and France by means of a line from Dover to Calais. Twenty-five nautical miles of No. 14 copper wire covered with ½-inch thickness of gutta-percha was then manufactured, the electrician’s tongue being the only test applied to some of the lengths. The shore ends for about two miles from each terminus consisted of a No. 16 B.W.G. conductor covered with cotton soaked in india-rubber solution, the whole being incased in a very thick lead tube. The rest of the line was composed of the gutta-percha insulated wire above described, with 30-pound leaden weights fastened to it at 100-yard intervals, the laying vessel having to be stopped each time one was put on. The submersion of the line was successfully effected, but it only lived to speak a few more or less incoherent words—one being a short complimentary communication to Louis Napoleon Bonaparte, shortly afterward Emperor of the French. It subsequently transpired that a Boulogne fisherman had hooked up the line with his trawl, “mistaking it for a new kind of seaweed!” This enterprise excited little attention at the time. It was, in fact, regarded as a “mad freak” and even as a “gigantic swindle.” When accomplished, The Times remarked, in the words of Shakespeare, “The jest of yesterday has become the fact of to-day”; and a few hours later it might with equal truth have been said that “the fact of yesterday has become the jest of to-day!” The feasibility of laying such a line and of transmitting electric signals across the Channel had, however, been proved. The signals obtained had, moreover, the effect of eradicating the then very prevalent belief that, even if the line were successfully submerged, the current would become dissipated in the water. It now remained to find a satisfactory method of protecting the insulated conductor from injury during and after laying. The excellence of the insulating material was recently testified to when some portions were recovered.
Though the above line was not, practically speaking, turned to any account, it was by no means abortive, for the signals it had conveyed were sufficient to “save the concession,” which was renewed by the French Government on December 19, 1850. But the previous failure had made capitalists distrustful; and only some weeks before the expiration of the time limit the necessary funds had not been raised.
Dover-Calais, 1850-’51.—The undertaking was saved by the energy and talent of one man, Mr. T. R. Crampton, an eminent railway engineer. He raised the necessary capital (£15,000), putting his own name down for half this amount and being joined by Lord de Mauley and the late Sir James Carmichael. He (Mr. Crampton) also settled the type of cable to be laid—based on the iron pit-rope; this, in one form or another, practically remains the type of to-day. The cable contained four copper conducting-wires of No. 16 B.W.G., each one covered with two layers of gutta-percha to No. 1 gage; these four insulated conductors, or “cores,” were laid together and the interstices filled up with strands of tarred Russian hemp. The outer covering consisted of ten galvanized-iron wires of No. 1 gage wound spirally round the bundle of cores; this armor was provided “with a view to protecting the insulated conductors from the strains and chafing which had so seriously interfered with the chances of the previous line.” The completed cable weighed about seven tons to the mile. It was coiled into the hold of an old pontoon hulk, which was then taken in tow by two steamers. A third tug to stand by, and a small man-of-war steamer to act as pilot, accompanied the laying expedition. The cable was landed at the foot of the South Foreland lighthouse and paid out toward Cape Sangatte, but the weather was less favorable than on the previous occasion; moreover, the weight of the cable—in the absence of efficient holding-back gear—caused it to run out too rapidly, notwithstanding the slight depth (some 30 fathoms) encountered. Added to this, the tugs drifted with the wind and tide. Thus when the vessels arrived within about a mile of the French coast no more cable was left on board, and a fresh length had to be procured and spliced on before the line was complete. This cable proved a lasting success: it underwent numerous and extensive repairs, and it was only quite recently that its abandonment took place.
Other Early Cables.—The success of Crampton’s line gave considerable impetus to submarine telegraphy. Similar enterprises sprung up on all sides; but many failures occurred before these operations came to be regarded as ordinary industrial undertakings. In the course of the following year (1852) three unsuccessful attempts were made to establish telegraphic communication between England and Ireland. In the first—between Holyhead and Howth—the cable was not heavy enough to contend with the rough bottom, and strong currents and disturbances from anchors experienced in these waters; but this undertaking is remarkable as being the only instance in which an effort was made to do without any intermediate serving between the insulated conductor and the iron sheathing. In the second attempt—between Port Patrick (Scotland) and Donaghadee (Ireland)—the cable consisted of a central copper conductor covered first with india-rubber, then with gutta-percha, and then hemp outside all. This cable, being far too light, was actually carried away by the strong tidal currents and even broken into pieces during laying. In the third endeavor, between the same two points, the arrangements for checking the cable while paying out being again inadequate, there was not sufficient to reach the farther shore. However, in 1853, a heavy cable, weighing 7 tons per mile, with six conductors, was successfully laid for the Magnetic Telegraph Company by the late Sir Charles Bright. This was in upward of 180 fathoms—the deepest water in which a cable was laid for some time—and proved a permanent success, forming the first establishment of telegraphic communication with Ireland. Only a year elapsed before it became evident that another cable was required to meet the traffic between England and the Continent, and an additional line was laid from Dover to Ostend. Anglo-Dutch and Anglo-German cables followed in due course; and in less than ten years from the commencement of its operations over the first Channel cable, the Submarine Telegraph Company (since absorbed by the state) was working at least half a dozen really excellent cables, varying from 25 to 117 miles in length, connecting England with the rest of Europe. During the next few years submarine communication was established between Denmark and Sweden, as well as between Italy, Corsica, and Sardinia; and between Sardinia and the north coast of Africa; but where successful, the measures adopted were, in the main, similar to those we have already described in connection with the preceding lines, though special conditions were, in some instances, the means of introducing certain modifications and improvements. Several serious failures were, however, experienced in the deep water of the Mediterranean which had a detracting effect—in the public mind—on the chances of the great undertaking which was to follow.
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